Source:

Response:

This claim is an example of the argument from
incredulity. One's inability to envision circumstances that lead to
complex instincts does not preclude such circumstances.

Not all instincts are complex. Some phobias, for example, are no more
than a basic emotional response to a simple stimulus, such as loud
sudden noise. And there is nothing to prevent the complex instincts
from arising gradually. For example, some bees only communicate
information about flower species to others in the hive (Dornhaus and
Chittka 1999). Complex instincts could arise via small steps such as
this.

References:

Further Reading:

Gould, James L. and Carol G. Gould, 1995. The Honey Bee. New York:
Scientific American Library.
Weiner, Jonathan, 1999. Time, Love, Memory: A great biologist and
his
quest for the origins of behavior. New York: Knopf.